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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_001_242">&nbsp;</a>NAME</h4><blockquote>
atof - convert a string to double-precision number
</blockquote><h4><a name = "tag_000_001_243">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="stdlib.h.html">stdlib.h</a>&gt;

double atof(const char *<i>str</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_001_244">&nbsp;</a>DESCRIPTION</h4><blockquote>
The call
<i>atof</i>(<i>str</i>)
is equivalent to:
<pre>
<code>
strtod(<i>str</i>,(char **)NULL),
</code>
</pre>
except that the handling of errors may differ.
If the value cannot be represented, the behaviour is undefined.
</blockquote><h4><a name = "tag_000_001_245">&nbsp;</a>RETURN VALUE</h4><blockquote>
The
<i>atof()</i>
function returns the converted value if the value can be
represented.
</blockquote><h4><a name = "tag_000_001_246">&nbsp;</a>ERRORS</h4><blockquote>
No errors are defined.
</blockquote><h4><a name = "tag_000_001_247">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_001_248">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
The
<i>atof()</i>
function is subsumed by
<i><a href="strtod.html">strtod()</a></i>
but is retained because it is used extensively in existing code. If the number
is not known to be in range,
<i><a href="strtod.html">strtod()</a></i>
should be used because
<i>atof()</i>
is not required to perform any error checking.
</blockquote><h4><a name = "tag_000_001_249">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_001_250">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="strtod.html">strtod()</a></i>,
<i><a href="stdlib.h.html">&lt;stdlib.h&gt;</a></i>.
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from Issue 1 of the SVID.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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